Knife-sharpening mechanism for cutting machines



Dec. 19, 1939. F,- J CLARK 2,183,787

KNIFE-SHARPENING MECHANISM FOR CUTTING MACHINES Filed March 9, 1938 3 Sheets-Sheet 1 QJMM% IN%ENTYOR 4124; 14M ywa ATTORNEYS Dec. 19, 1939. F. J. CLARK 3 3 KNIFE-*SHARPENING MECHANISM FOR CUTTING MACHINES Filed March 9, 1938 s Sheets-Sheet 5 INVENTOR ATTO R N EYS Patented Dec. 19, 1939 UNETED STATES KNIFE-SHARPENING MECHANISM FOR cur- TING MACHINES Frederick J. Clark, Buffalo, N. Y., assignor to Eastman Machine Company, Bufi'alo, N. Y.

Application March 9, 1938, Serial No. 194,895

Claims.

This invention relates more particularly to improvements in the knife-sharpening mechanisms of cutting machines of the portable cloth cutting machine type which have an upright, vertically reciprocating knife which can be caused to follow a desired pattern or line of cut in a lay of cloth or other material by appropriately moving and guiding the machine about upon the supporting table for the material. Such machines are commonly employed for simultaneously cutting a considerable number of superposed layers of material, and the cutting edges of the knives must be kept very keen or sharp. In order to maintain when cutting some kinds of material, it is necessary to sharpen the knives every few minutes during the cutting operation. Therefore, the sharpening mechanism is arranged on or made a part of the machine so that it is always available and capable of being readily and quickly operated for sharpening a knife with as little interruption as possible in the cutting operation.

Various sharpening mechanisms for the purpose have been devised and patented, nevertheless it has remained the usual practice to sharpen the knives by a hand-honing operation which, besides being relatively slow and requiring considerable skill upon the part of the operator,

frequently results in imperfect and irregular sharpening of the knife and undue wearing away thereof, and often does not produce the desired wide, thin edge bevel. Objectionable abrasion and wear of the machine standards and bases also result from hand honing.

Recently, however, a successful knife-sharpening mechanism for machines of the type mentioned, having power-driven means in the form of flexible, abrasive 'belts for sharpening the knife, has been devised. Patent No. 2,060,197, issued to M. Greenbaurn November 10, 1936, discloses such a sharpening mechanism, and it is one purpose of the present invention to improve sharpening mechanisms of this type employing flexible knife-sharpening belts.

Other objects of the invention are to provide an efiicient, practical sharpening mechanism of the power-driven sharpening belt type mentioned, which is of novel, economical, strong and durable construction; also to provide an improved and effioient knife-sharpening mechanism for machines of the type mentioned which is so constructed and arranged that it forms a permanent part of the machine without hindering in any way the use of the machine for cutting or obstructing the operators View of the work, and which has power-driven, knife-sharpening means adapted to be moved lengthwise along the knife for sharpening it throughout its effective length; also to provide improved motor-operated drive mechanism for the knife-sharpening means or belts; also to provide an improved knife-sharpening mechanism which constitutes a complete separable unit mounted on the cutting machine .so that it can be readily applied .to and removed from the machine as a-unit, and is adapted to be applied with the minimum of change to cutting machines already in use; which includes convenient, readily operablemeans for placing the sharpening means into and out of operative positionand starting and stopping the drive mechanism thereof; which includes improved means for guiding the sharpening means during their lengthwise movement along the knife edge; and also to provide knife-sharpening mechanism for machines of the type mentioned which has the other features of improvement and advantage hereinafter described and set forth in the claims:

In the accompanying drawings:

1 is a side elevation of-an upright reciprocating knife cutting machine, equipped with knife-sharpening mechanism embodying our invention, a portion of this mechanism being shown in vertical section.

Fig. 2 is av front elevation, partly in section thereof, and, like Fig. 1, showing the upper inoperative position. of the grinding means.

Fig. 3 is=a transverse, sectional elevation thereof on line 3-3, Fig. 1, and showing the grinding means lowered.

Fig. 4 shows .in front elevation the carriagelatching means in position about tocam the oarriage up to its inoperative position.

Fig. 5 is a view showing the, grinder carriage in plan and the knife standard in horizontal section.

Fig. -6 is a sectional plan view on line 6--6, Fig. 2.

Fig. 7 is a transverse sectionof the grinding means on line 1-1, Fig. 5.

Fig. -8 is a fragmentary inside elevation showing one of the sharpening belts and its presser finger, and one guide shoe.

Figs. 9 and 10 are sectional plan views on lines .99 and l0- I.U, Fig. 3, respectively. I

Except with respect to the knife-sharpening mechanism, and associated parts, this invention is not concerned with the construction of the cutting machine, and it may be of the construction illustrated in the drawings or of other suitable construction. As shown in the drawings,

the machine comprises a base l adapted to rest and be moved about upon the table or supporting surface for the material to be out, an upright, slender standard l8, which is rigid with and rises from the base and supports a stationary frame I! which houses an electric or other motor at H! for driving the vertical knife IS. The knife is reciprocated in a vertical guide slot in the front of the standard by the motor through drive con-.

nections comprising a slide 28 to which the knife is secured at its upper end and which is reciprocated in a suitable guide on the frame by a pitman 2! connecting it to the crank pin of a crank wheel 22 secured to the front end of the rotary shaft of the motor. The usual presser foot 23 is fixed to the lower end of a rod 24 which extends vertically in frontof the knife l9, thus forming a guard for the knife, and is adjustable vertically, as in guides 25 and 25a on the front of the housing 33, to support the presser foot at different elevations suited to different lays of material to be cut. The rear end of the presser foot is bifurcated and straddles the front edge portion of the standard, thereby assisting in preventing lateral deflection of the guard rod. The guard rod may be releasably held in different adjustments, as by a latch or device 28 carried by the up-turned front endof a release lever 21, and releasably pressed into holding engagement with the toothed side of the guard rod by a spring 28. The lever 21 is pivoted at one side of the machine With its other end extending rearwardly to a position where it can be readily actuated for moving the latch to release the pressure foot, by the operators hand which grasps the machine handle.

Preferably, the knife grinding or sharpening means comprises two grinding elements 30 and 3|, each consisting of a flexible belt or strip having an abrasive grinding surface of carborundum or other suitable abrasive material, which belts are disposed at opposite sides of the knife in such a way that their abrasive surfaces can be caused to travel in sharpening contact with opposite sides of the front edge portion of the knife. These belts are power-driven, preferably by the knife-operating motor of the machine, so that the runs or portions of the belts which contact with the knife, travel forwardly past the latter, and they are mounted on a carriage or support 32 arranged for movement up and down parallel with the knife edge to adapt the belts to sharpen the knife throughout its effective cutting length. 7

Said knife-grinding means or elements, together with the drive means therefor, and other operative parts of the sharpening mechanism are preferably mounted on and carried by a frame part or housing 33 which is stationarily but removably secured at the front of the machine, as by fastening screws 34 screwed into the front of the stationary frame I! so that the sharpening mechanism is applied to and removable as a unit from the machine. The housing 33 also serves as the cover for the crank wheel 22, pitman and other parts of the knife-operating mechanism.

Improved drive mechanism for the knifegrinding means or elements is employed, preferably constructed as follows: Arranged in the housing 33 in front of the crank wheel is a vertical shaft 35 which is journalled at its lower portion in a suitable bearing 38 at the lower end of the housing 33. The shaft extends up through a shaft opening in the upper end of the housing and through a bearing 31 in a gear casing 38 arranged above the housing 33 to move vertically toward and from the same on suitable guides, such as fixed posts 39 projecting up from the housing 33 through guide holes in the gear casing 38. Journalled in the gear casing 38, preferably in suitable ball bearings 40, is a horizontal shaft 4| on the inner end of which is fixed a wheel 42 adapted to be driven by engagement with the crank wheel 22, which may be provided with a peripheral band or tire 42a of rubber or other suitable friction material to ensure effective driving of the wheel 42 by frictional contact therewith. The wheel 42 is adapted to be pressed into driving engagement with the crank wheel, preferably by coil springs 43 which surround the posts 38 between the top of the gear casing 38 and nuts on the upper end of the posts and tend to move the gear casing downwardly to engage the wheel 42 with the crank wheel 22. The shaft 4| is geared at its front end to and drives the vertical shaft 35, preferably by spiral pinions 44 and 45 secured respectively to the shaft 4| and the upper end of the shaft 35. At its lower end, the shaft 35 is geared by intermeshing' pinions 48 and 41 to and drives a second vertical shaft 48 arranged at one side of the shaft 35 and journalled to rotate and move lengthwise in suitable bearings 49, 49a and 49b in the housing 33. The pinion 48 is confined vertically in a chamber in the bottom of the housing 33 and is splined to the shaft 33 so as to allow a limited, lengthwise movement of the shaft in the pinion. The pinion 41 is splined to the shaft 48, as by a key 5| in the pinion projecting into a longitudinal keyway in the shaft 48, so that while the shaft 48 is driven by the rotation of the pinion, it is adapted to move vertically through the pinion, which is held from vertical movement in the housing chamber in which it is located. The shaft 48 extends down through a shaft opening in the bottom of the housing 33 and also preferably is adapted, when in its raised position, to extend up through the gear casing 38 into a tube 52 projecting up from the gear casing 38. This tube is long enough to enclose and guard the upper portion of a shaft 48 of sufiicient length to allow such vertical movement of the grinding means as required to sharpen a knife of the maximum required length.

The lower end of the shaft 48 extends through and is journalled in a bearing 35 in the vertically movable carriage 32 for the grinding means or belts. A drive pulley 58 for the sharpening belt 38 is fixed to the shaft 48 below the carriage 32 and a drive pulley 51 for the other belt 3| is fixed to a short vertical shaft 58 suitably journalled in the carriage 32 parallel with the shaft 48, this shaft 58 being geared to and driven from the shaft 48 by intermeshing pinions 59 and 80 fixed on said shafts and confined within a chamber in the carriage 32. The grinder carriage is thus held from longitudinal movement relative to the shaft 48, but is adapted to be moved with the shaft 48 up and down along the edge portion of the knife.

The belt 38 passes around its drive pulley and an idler pulley 8|, and the other belt passes around its drive pulley and an idler pulley 82.

The idler pulleys are supported by fixed legs 63 projecting rearwardly from the grinder carriage 32 and straddling the knife standard, and each idler pulley is preferably journalled on a slide 84 movable toward and from the companion drive 2,183,787 pulley on its supporting leg and y'ielding'ly pressed rearwardly by a spring 65 for .maintaining the belt under suitable tension, and permitting removal and renewal of the belts by moving the idler pulleys to slacken the belts.

As shown, the two sharpening belts are disposed at difierent levels, or one above the other, and are yieldingly pressed into grinding or sharpening contact with opposite sides of the edge portion of the knife by spring pressed members or fingers 56, which may be pivoted on the carriage legs -63 and provided with springs til coiled about the finger pivots, which press the front or free ends of the fingers against the inner surfaces of the belts and press the belts yieldingly against the knife. These pressure fingers are so shaped that their free end portions which engage the belts will hold the engaged portions of the belts at the requisite angles where they contact with the opposite sides of the knife to insure grinding or sharpening the knife so as to maintain thereon a wide, thin, bevelled edge which is very sharp or keen, and remains sharp for the maximum time.

The grinder carriage 32 is guided in its vertical movements, preferably by slotting the front end of the carriage at H3 to embrace and slidably engage the vertical guard rod 2d, and by providing guide shoes I! on the carriage arranged to slidably and preferably yieldingly engage the knife standard. As shown, these guide shoes are formed by spring strips fixed at their forward ends to the carriage legs 63 and project rearwardly at opposite sides of the standard with inwardly bent or curved rear portions which bear yieldingly against the rounded rear edge of the standard. Since the guide shoes more or less surround or hug the rear edge portion of the standard, th y tend to prevent forward movement of the carriage and sharpening belts away from the knife edge, and so maintain the belts in the intended sharpening contact with the knife during the operation of the sharpening mechanism.

By the described drive mechanism, the grinding means or belts are driven rapidly and positively and, while running, they may be moved up and down along the edge of the knife for shrapen- 'ing it throughout its eifective length by moving the grinder carriage up and down, which is permitted by the lengthwise movement of the vertical shaft 48 in its bearings. The carriage is guided in its up and down movements by the shaft 58 supplemented the guiding engagement of the carriage with the guard rod and of the spring guide shoes H with the knife standard. lhe spring shoes ll, while preventing objectionable lateral looseness or movementof the grinder carriage, nevertheless permit a slight lateral yielding of the carriage and belts. The spring guide shoes in cooperation with the spring pressure fingers ES act to press the belts yieldingly against the knife and allow sumcient give of the belts to cause them to automatically maintain correct grinding relation to the knife edge. Thus, a proper edge is insured and possible variations or inaccuracies of form or relation in the carriage guides or irregular hand pressures on the carriage during its up and down movements along the knife edge are compensated for and prevented from forming an irregular or non-uniform edge on the knife.

For moving the grinder carriage up and down, it is preferably provided with a forwardly projecting, rigid finger piece it in the form of a ring whichisadapted to beconveniently grasped lever into engagement and thus throw the wedges pressing the belts against the knife. When the carriage.

In the normal operation of the machine for cutting material, the grinder carriage with its grinding means or belts is held in its uppermost position, shown in Fig. 1, where it is out of the way and does not interfere with the cutting operation of the knife nor obstruct the view of the operator in using the machine, at which time it is carriage in its uppermost position. As shown,

this latch consists of a lever suitably pivoted at l at its lower portion on the front of the grinder carriage andhaving at its upper portion a forwardly projecting finger piece l7 for moving the with a fixed stud it? projecting forwardly from the housing 33 above and adjacent the carriage when the latter is raised. The latch has a lateral, downwardly facing earn between the thumb and finger for moving the are edge 79 which, when the grinder carriage has been raised nearly to its uppermost position. is adapted to be swung into engagement with the stud 78, and by pressure on the latch finger piece acts on the stud to cam the grinder carriage up to its uppermost position, where it will be held by the engagement of the stud 78 in a seat or depression 8!] j in the latch at the end of the cam edge. The.

latch is adjacent the carriage finger piece and can be very conveniently actuated to thus cam the carriage up by lateral pressure on the latchfinger piece Tl with one of the fingers of the same hand with which the operator grasps the carriage finger piece to raise the carriage. Likewise, the carriage can be readily unlatched and moved with one hand for sharpening the knife.

This final upward movement of the grinder carriage by the cam latch is utilized. follows, to disengage the wheel 42 from the crank wheel 22 grinding means drive out of action. When the sharpening mechanism is in use, with the grinder carriage below its uppermost position, the lower end of the shaft 35 projects downwardly slightly out of the bottom of the housing in which position it is held by the downward pressure of the springs 43 on the gear casing 36. In camming the grinder carriage up to its inoperative position, the top of the carriage engages the projecting lower end of the shaft '35, and lifts the shaft to slightly, and the engagement of the upper end of the shaft with a fixed part at the top of the gear casing 38 will raise the latter and lift the drive wheel ll out of driving engagement with the crank wheel, and stop the grinding means.

In order to hold the sharpening means or belts out of contact with the knife when in their raised. inoperative position, and thus p event possible cutting of the belts or objectionable wear on the upper portion of the knife, a belt-spreading member or wedge ti is fixed to and projects downwardly from the lower end of the housing 553 in front of the knife. When the grinder carriage is being raised to its inoperative position, the point of this wedge enters between upward projections 82 on the front ends of the belt presser fingers and them apart so as to prevent them from pressure of the fingers 66 on the belt is thus removed, the tendency of the inner runs of the belts to straighten under the tension of the idler pulleys thereon pulls the abrasive surfaces of the belts out of contact with the knife.

When using the machine for cutting, the grinder carriage is retained in its raised, inoperative position by the latch 15, where it is out of the way. When the knife requires sharpening, it is only necessary to release and lower the presser foot to its lowest position and release the latch l5, and move the grinder carriage down and up along the reciprocating knife by means of the carriage finger piece 13. Only one or two down and up movements of the grinding means is usually necessary, and at the end of the last up movement, the grinder carriage is latched in its raised, inoperative position, as explained, and the machine is ready to continue its cutting.

I claim as my invention:

1. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of grinding means for said knife, a carriage supporting said grinding means and movable for shifting said means lengthwise along the knife edge, and drive mechanism for said grinding means comprising a shaft extending in an up and down direction above said carriage, a driving motor operatively connected with the upper portion of said shaft, a vertical shaft arranged at one side of said first shaft to move with said carriage lengthwise of the knife edge, gear wheels operatively connecting the lower portion of said first shaft and said vertical shaft for rotating the latter, said vertical shaft being rotatable with but movable axially relatively to one of said gear wheels and a drive connection from said vertical shaft to said grinding means.

2. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of flexible abrasive band means for sharpening said knife, a vertically movable carriage supporting said means, and drive mechanism for said means comprising a shaft extending in an up and down direction above said carriage, a driving motor operatively connected with the upper portion of said shaft, a vertical shaft arranged at one side of said first shaft to move with said carriage lengthwise of the knife edge, gear wheels operatively connecting the lower portion of said first shaft and said vertical shaft for rotating the latter, said vertical shaft being rotatable with but movable axially relatively to one of said gear wheels and a drive connection from said vertical shaft to said means.

3. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of flexible sharpening belts for the knife at its opposite sides, a vertically movable carriage supporting said belts, and drive mechanism for said belts comprising a shaft extending in an up and down direction above said carriage, a driving motor for said belts operatively connected with the upper portion of said shaft, a vertical shaft rotated by gear wheels connecting it with the lower portion of said first shaft and arranged to move with said carriage relatively to said gear wheels lengthwise of the knife edge, and drive connections from said vertical shaft to said belts.

4. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of a. grinding element for said knife, a vertically movable carriage supporting said element, drive mechanism for said element comprising a shaft extending in an up and down direction above said carriage, a driving motor, releasable drive means from said motor to said shaft, a vertical shaft rotated by driving connection with said first shaft and arranged to move with said carriage lengthwise of the knife edge, a drive connection from said vertical shaft to said grinding element, and,

means for moving said carriage lengthwise along the knife edge, said first shaft being shifted by movement of said carriage for actuating said releasable drive means for stopping the grinding element.

5. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of a grinding element for said knife, a vertically movable carriage supporting said element, drive mechanism for said element comprising a shaft extending in an up and down direction above said carriage, a driving motor, releasable drive means from said motor to said shaft, a vertical shaft rotated by driving connection with said first shaft and arranged to move with said carriage lengthwise of the knife edge, a drive connection from said vertical shaft to said grinding element, means for moving said carriage lengthwise along the knife edge, and a latch for releasably retaining said carriage in an upper inoperative position, the movement of the carriage to the latched position actuating said releasable drive means through the medium of said first shaft for stopping the grinding element.

6. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, of a grinding element for said knife, a vertically movable carriage supporting said element, drive mechanism for said element comprising a shaft extending in an up and down direction above said carriage, a driving motor, releasable drive means from said motor to said shaft, a spring tending to maintain driving relation between said releasable drive means and the motor, a vertical shaft rotated by said first shaft and arranged to move with said carriage lengthwise of the knife edge and operatively connected to said grinding element, means for moving said carriage lengthwise along the knife edge, and a latch for releasably retaining said carriage in an upper inoperative position, the movement of the carriage to the latched position actuating said releasable drive means through the medium of said first shaft for stopping the grinding element, and the unlatching of the carriage permitting movement of releasable drive means by said spring for setting said drive mechanism in motion.

'7. In a cutting machine, the combination with a vertically reciprocating knife having a vertical cutting edge, of flexible abrasive band grinding means for said knife, a vertically movable carriage supporting said grinding means, means for moving said carriage vertically along said knife edge, and drive mechanism for said grinding means comprising a vertical shaft extending upwardly from a point above said carriage, a driving motor operatively connected with the upper end of said shaft, a vertical shaft arranged at one side of said first shaft to move vertically with said carriage, gear wheels operatively connecting the lower end of said first shaft and said vertical shaft for rotating the latter, said vertical shaft being rotatable with but movable axially relatively to one of said gear wheels and a drive connection from said vertical shaft to said grinding means.

8. In a cutting machine, the combination with a vertically reciprocating knife having a vertical cutting edge, of a grinding element for said knife, a vertically movable carriage supporting said element, means for moving said carriage vertically along said knife edge, drive mechanism for said element comprising a motor, a vertical shaft arranged to move vertically with said carriage and operatively connected to said grinding element, releasable drive means from said motor to said shaft, a cam latch operable to lift said carriage and releasably retain it in an upper inoperative position, and means actuated by the lifting of the carriage by the latch to release said releasable drive means from said motor.

9. In a cutting machine, the combination with a vertically reciprocating knife having a vertical cutting edge, of a grinding element for said knife, a vertically movable carriage supporting said element, means for moving said carriage verti-' cally along said knife edge, drive mechanism for said element comprising a motor, a vertical shaft arranged to move vertically with said carriage, and operatively. connected to said grinding element, releasable drive means from said motor to said shaft, a cam latch operable to lift said carriage and releasably retain it in an upper inoperative position, means actuated by the lifting of the carriage by the latch to release said releasable drive means from said motor, and spring means which when said latch is actuated to release the carriage establishes driving relation between said releasable drive means and the motor.

10. In a cutting machine, the combination with a vertically reciprocating knife having a vertical cutting edge, of a grinding element for said knife, a carriage which supports said grinding element and is manually movable vertically along the knife edge, a driving motor and mechanism including a releasable element for driving said grinding element, and latch means constructed and operable to forcibly lift the carriage to and releasably retain it in an upper inoperative position and release said releasable driving element from the motor, said latch being arranged adjacent said carriage in position to be actuated by a finger of the hand which moves said carriage vertically. Y

11. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, and a vertical standard having a guide slot in its front edge for said knife, of a grinding element for said knife, a carriage supporting said grinding element, means for yieldingly pressing said grinding element against the edge portion of the knife, drive mechanism for said grinding element including a vertically movable vertical shaft, means for moving said carriage lengthwise along said knife edge, and guide shoes comprising spring strips fixed to said carriage and straddling said standard and bearing yieldingly against the rear edge of the standard at opposite sides thereof for cooperating with said vertical shaft in guiding the grinding element along the knife edge and resisting movement of the grinding element forwardly away from the knife.

12- In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, and a vertical standard in which said knife is guided, flexible abrasive belts arranged to contact with opposite sides of the edge portion of the knife, a carriage supporting said belts, drive mechanism for said belts including a vertical shaft movable vertically with said carriage, means for moving said carriage and belts lengthwise along the knife edge, means for pressing said beltsyieldingly against the edge portion of the knife, and spring guide shoes on said carriage bearing yieldingly against opposite sides of said standard for cooperating with said vertical shaft in guiding said belts lengthwise along said knife edge. I

13. In a cutting machine, the combination with a vertically reciprocating knife having a substantially vertical cutting edge, and a vertical standard in which said knife is guided, flexible abrasive belts arranged to contact with opposite sides of the edge portion of the knife, a carriage supporting said belts, drive mechanism for said belts including a vertical shaft movable vertically with said carriage, presser vfingers on said carriage for yieldingly pressing said belts into sharpening contact with said knife, guide means on said carriage slidably engaging said standard for cooperating with,said vertical shaft in guiding the carriage and belts lengthwise along the knife edge, and a spreader arranged to engage and spread said presser fingers apart for preventing sharpening contact of the belts with the knife when the carriage is in an upper inoperative position.

14. In a cutting machine, the combination with I element, latch means comprising an operating member and means actuated thereby which lift said carriage to and releasably retain it in an upper inoperative position, and means actuated by the lifting of the carriage by said latch means constructed and arranged to arrest the motion I of said drive mechanism.

15. In a cutting machine, the combination with a knife which has a substantially upright cutting edge and is reciprocated substantially in the lengthwise direction of said edge, of grinding means for the knife, a carriage supporting said grinding means, means for moving said carriage and grinding means lengthwise along the knife edge, a motor and drive mechanism for said grinding means, latch means constructed and operable to lift said carriage to and releasably secure it in an inoperative position, and means actuated by the operation of said latch means for securing and releasing said carriage constructedand arranged to stop and start said drive mechanism. ,v I

FREDERICK J. CLARK. 

